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Introducing the differential design concept of functional gradient into mass concrete structures is a feasible design concept that can meet the requirement of crack resistance and internal hydration heat reduction for mass concrete in cold regions. This study analyzed functionally graded concrete’s long-term performance and durability behavior through experimental tests. Based on various concrete mix proportion designs, six concrete groups were selected to test. The shrinkage performance tests were conducted according to the specifications, and early crack resistance tests were also carried out. In addition, the crack development characteristics of concrete with different mix proportions were compared and analyzed, and the impermeability, frost resistance, and carbonation resistance tests were conducted. The test results show that concrete’s long-term performance and durability can be effectively improved by adopting the functional gradient concrete design. The functional gradient concrete adds an anti-freezing polycarboxylate superplasticizer, steel fiber, and polypropylene fiber. Therefore, it can better meet the actual needs of mass concrete structures in cold regions. The drying and autogenous shrinkage rates of mass concrete structures mixed with a composite water reducer were significantly reduced. As a result, this method effectively improved the microporous structure, reduced the loss of dynamic elastic modulus, and improved the anti-freezing performance of concrete of various strength grades. Furthermore, adding steel-like fiber and monofilament polypropylene fiber to the concrete outside the structure can improve the crack resistance of concrete and effectively inhibit the occurrence and development of dry shrinkage and early cracks. Therefore, it can better meet the actual needs of mass concrete structures in cold areas.

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